Corrosion is an electrochemical process that causes the degradation of metal materials due to their interaction with the environment. It is a complex process influenced by physical, chemical, metallurgical, electrochemical, and thermodynamic factors. Cathodic protection is a technique used to reduce corrosion of metal surfaces by making them the cathode of an electrochemical cell. It involves connecting the metal structure to be protected to an external source of electrons (anode) to prevent corrosion at the anode site. Common methods of cathodic protection include impressed current cathodic protection using external power sources and sacrificial anode cathodic protection using reactive metals like zinc and magnesium as anodes.